Medium speed printer



y 29, 1958 R. c. STIEFEL 2,845,019

MEDIUM SPEED PRINTER Filed May 16, 1955 '7 Sheets-Sheet l 7 Sheets- -Sheet 3 l :Illlllll INVE/VTd/Q Q w A, a n. n Y

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1 k r roam/5v July 29, 1958 R. c. STIEFEL MEDIUM SPEED PRINTER Filed May 16, 1955 July 29, 1958 R. c. STIEFEL MEDIUM SPEED PRINTER Filed May 16, 1955 7 Sheets-Sheet 4 R. C. STIEFEL MEDIUM SPEED PRINTER July 29, 1958 7 Sheets-Sheet 5 Filed May 16, 1955 :oiooop n I II I mvllllllll r July 29, 1958 R. c. STIEFEL MEDIUM SPEED PRINTER 7 Shee'tS-Sheec 7 Filed May 16, 1955 United States Patent "ice MEDIUM SPEED PRINTER Rudy C. Stiefel, Woodside, N. Y., assignor to Sperry Rand Corporation, a corporation of Delaware Application May 16, 1955, Serial No. 508,427

11 Claims. (Cl. 101-96) The present invention relates to printers operable at high speeds.

One object of the present invention is to provide a printer, which although occupying a comparatively small space, can operate a great deal faster than teleprinters and electric typewriters now in operation, which is comparatively simple and highly dependable, and which although printing at high speeds, has its critical parts operating at low speeds.

In accordance with the present invention, the printing function of the present machine is accomplished by two operations, namely selection of characters and printing of characters. A time delay is introduced between selection and printing to afford ample time for selection without undue stresses in the mechanism.

More specifically, the printing is effected in accordance with the present invention by a deck of similar printing wheels mounted on a common continuously rotating shaft and carrying duplicate sets of printing characters. These printing wheels are mounted to rotate with the shaft but have slip connections therewith permitting the wheels to be stopped independently of each other without stopping the shaft. Selection is made by a selector device which acts on the wheels successively to cause said wheels to stop in positions according to the character signal transmitted to the machine. In the position in which the Wheel is stopped by the selector device, the selected character thereof lies on the line of action of a printing device. This printing device follows the selector device along this line of action and operates to impress the selected character along this line on a record sheet. A delay is introduced between the reception of a character sig nal causing the actuation of the selector device and the operation of the printing device, in order to allow the character wheels sufficient time to be positioned. The delay offset between the selector device and the printing device corresponds to a definite number of signals. At the beginning of printing operations, the character signals transmitted to the machine cause the selector device to operate successively on the character wheels, so that each signal causes a selection on a corresponding wheel. During this initial phase, the printing device remains inactive. After a predetermined number'of signals have been received and a corresponding number of selections have been made on the wheels, the printing device starts to operate. Thereafter, the printing device operates successively on the selected wheels at'the same speed as the selector device but at a later phase corresponding to the lag set into the machine by the offset described. This allows the wheels ample time to accelerate and decelerate into selected positions without undue speeds or stresses.

The printing machine is provided with means for transmitting line function signals by which the printing operation is transferred to a next successive line and input stop and start controls by which during the periods when the selector device or printing device is shifting for the 2,845,019 Patented July 29, 1958 next line operation, stop signals are sent out to hold up the transmission of input information signals. After a delay sufficient to permit the selector device or printing device to return for the next line operation, antinput start signal isgenerated causing the printing and selection operations to resume. -In this manner, the necessary lag between selection: and printing is maintained.

As a further feature, tabulating controls are provided operating in conjunction with the input stop and start controls described above, to permit the tabulating of characters or figures in predetermined columns on the record sheet.

By means of the printing machine described, it is possibleto operate at a speed ofas high as 50 to 100 characters .per second- Various other objects, features and advantages of the invention are apparent from the following particular description and from the accompanying drawings, in which Fig. l is a side elevation of the printer embodying the present invention;

Fig. 2 is a rear elevation of the printer;

Fig. 3 is the top plan view of the'printer;

Fig. 4 is the end view of the wheel assembly with associated selector and printing parts and taken approximately along 'the'lines 4'-4 of Fig. 5;

Fig. 5 is the rear elevation of the wheel assembly with associated selector and printing parts taken approximately along the lines-55 of Fig. 4;

Fig. 6 is the front elevation of the wheel assembly with associatedselector and printing parts shown in Fig. 4;

Fig. 7 is a detail section of the wheels with associated selector parts; I

Fig: 8 is a radial detail section of the wheels with associated selectorparts taken approximately along the lines 8'8 of Fig. 7;

Fig. 9 is a diagram of a delay counter register which may be employed as part of the printer; and

Fig. 10 is a diagrammaticshowing of the various parts of the printer indicating their functional relationship.

Referring to" the drawings, the printing machine itself comprises a deck of character bearing wheels 10 (Figs. 4, 5, 6 and 7) -(70 being-shown) all of thesame size and each carrying a. series'of imprinting characters 10a arranged along a section l-l of its periphery. These wheels 10 allcarry thesame characters similarly arranged. In a specific. example, the wheels -10 may carry between 48 and 64 characters,,including letters and numerals. For the purpose of illustration, the drawings show each wheel 10 carrying 48 different characters.

The wheels 10 are .all centrally mounted on a shaft 12, which is constantly rotated from ,a suitable drive 13 (Fig. "10) and the'connection' between each wheel and the shaftis such, asto permit the wheel to be stopped independently of .the other wheels upon selection, without stopping the shaft. To that end, this connection is a friction slip device, which" may comprise a bushing 14 (Fig. 4) aflixed toieach wheel 10 at the center and embracing the shaft 12 with suflicient friction to cause said wheel to rotatewith said shaft, when.said wheel is not blocked but to ,permitsaid wheel to be stopped in selected angular position without stopping the shaft The printingoperation is .carried on against a record sheet 16 (Figs. 4 and 6) .along a line of action A parallel to. the wheel shaft 12 in amanner to be more fully described. For stopping the wheels 10 in position to cause selected characters thereon'to come to rest along the printing line of action A, each ofsaid wheels hasa recess .17 (Figs. 4 and; 7 on one side'extending around the entire periphery of. the wheel except in one section to provide a radial stop 18 faced with a bumper pad 20 made'ofresilient material,.such as neoprene. For c0- operation with this stop 18, there is provided a fixed stop pin guide 21 (Figs. 4'and 7) in the form of a sector arm, partially encircling each wheel 10 in a region diametrically opposite the line of printing action A and arranged concentrically with said wheel. This stop pin guide 21 radially holds a series of spaced stop pins 22 corresponding in number to the number of characters on the wheel 10, i. e. 48 stop pins in the example illustrated. A spring 23 encircles each of the pins 22 and normally urges it radially outwardly, with the end section of the pin projecting beyond the outer periphery of the stop pin guide 21, to permit it to be depressed inwardly by a selecting operation to be described. This selecting depressing op eration causes the radially inner end section of the stop pin 21 to project into the peripheral recess 17 of the I tating wheel 10 in the path of the stop 18. When the wheel 10 is immobilized by engagement of its stop 18 with the depressed stop pin 22, the character thereon which lies on the line of action A, will be the selected character. The wheel 10 will remain in this immobilized position, until the printing device to be described reaches this character and imprints it on the record sheet 16, whereupon the printing device moves on to the next wheel stopped in selected position.

To assure the maintenance of the depressed selected stop pin 22 for the wheel 10 in depressed position until the printing device has reached this wheel, there is provided an arcuate lock bar 25 (Figs. 4, and 7) on the outer periphery of each stop pin guide 21 concentric therewith and having a series of openings 26 through which the stop pins 22 project respectively with clearances 27 on one side of the pins. This lock bar 25 is mounted to move a small distance circumferentially along the fixed stop guide 21 and is urged towards one limiting position by a spring 28. A bevel catch 30 on each stop pin 22 rides across the edge of the corresponding opening 26 as the pin is depressed by selection, causing the lock bar 25 to be moved circumferentially along its arcuate length against the action of the spring 28. This allows the selected stop pin 22 to be depressed until the catch 30 extends radially inwardly of the lock bar 25, whereupon the lock bar will be released by the action of the spring 28 in position to latch the selected stop pin 22 in depressed position, until liberated by the next pin depressing operation. This movement of the lock bar 25 not only causes the selected stop pin 22 to be latched in depressed wheel stopping position, but also releases the previously depressed and latched stop pin 22 under the action of its encircling spring 23, so that the latter stop pin is restored into radially outward inactive position.

To depress any stop pin 22 on a wheel according to a selection, there is provided an arcuateselector arm or ring 31 (Figs. 4 and 5) concentrically encircling the stop pin guides 21. This selector'ring 31 is just wide enough to span at the most only a few stop pin guides 21 and has a base 32 supported to move the selector ring step by step into stop pin selecting positions in relation to the stop pin guides 21, as will be more fully described. Carried on the selector ring 31 are-spaced spring-pressed selector plungers 34 corresponding in number to the number of characters on each wheel 10, i. e. 48 plungers in the specific example illustrated. The heads 35 of the plungers 34 normally project radially outwardly beyond the selector ring 31 to permit the plungers to be depressed by a positioning device 36 to be described. These plungers 34 are arranged in radial alinement with the stop pins 22 respectively of any wheel 10 opposite which the selector ring 31 has been stopped temporarily for selection and are close enoughto said pins, so that upon depressing a plunger 34 through the actionof the positioning device 36, the depressed plunger will in turn depress the corresponding stop pin 22 and thereby stop the wheel 10 carrying said stop pin in selectedposition.

The selector ring 31 is moved step by step into successive selecting positions opposite the stop pin guides 21 by any suitable drive means, in response to character and space function pulses or signals sent from a suitable transmitter, as will be more fully described. The specific drive means shown for purposes of illustration, comprises a conveyor 40 (Fig. 5) having a chain 41 passing over sprocket wheels 42 and 43. The sprocket wheel 42 is driven from a drive 44 through a reversing gear unit 45 operable into either one of two positions to drive the conveyor in either direction and controlled in a manner to be described. The connection from the output of the reversing gear unit 45 to the sprocket wheel 42 is through a Geneva mechanism 46 to assure a predetermined movement of the selector ring 31 for every character or space function pulse or signal received. In response to each character or face function pulse, the drive pin carrying disk 47 to the Geneva mechanism 46 is triggered to rotate one revolution and no more through the usual one revolution clutch device of the well known type, and this causes the conveyor 40 to be moved one step through a predetermined distance to bring the selector ring 31 opposite the next stop pin guide 21 in selecting position with respect thereto.

The plungers 34 on the selector ring 31 are selectively depressed through the positioning bar device 36 comprising a series of bars 51 corresponding in number to the number of characters on each printing wheel 10, i. e. 48 for the 48 characters in the specific example described, and extending parallel to the shaft 12 of the wheels 10 in an arcuate row around the selector ring 31 and concentric therewith. These bars 51 are positioned radially opposite the plungers 34 respectively carried by the selector ring 31, so that upon operation of any one bar in a radially inward direction, a corresponding plunger 34 upon said selector ring is depressed. For so operating the positioning bars 51 selectively, each of said bars is connected at its ends to the plungers of two solenoids 52, which in turn are controlled from the character and spaced function signals, as will be more fully described.

The character pulses are sent out by the transmitter, the pulses being all the same for the dilferent characters, but being transmitted by separate leads corresponding to the dilferent characters, so that in the specific form of the invention illustrated, there would be forty-eight pairs of leads. Each pair of leads would control the energization of a corresponding pair of solenoids 52 connected to a positioning bar 51, which will select the character on a wheel 10 corresponding to the character signalled through said leads. These pulses may be made to act directly on the corresponding solenoids 52 after the necessary amplification, or may be made to control the operation of a relay switch in the circuit of the solenoids.

After selection of the character on a wheel 10 has been made in the manner described, and the wheel has been brought to a stop by the depression of the stop pin 22 corresponding to this character into wheel blocking position, a printing device 53 (Figs. 4 and 6) moving along the printing line of action A comes into play to imprint the selected character on this line of action onto the record sheet 16. The record sheet 16 is a fan-fold paper sheet held in an input tray stand 54 (Fig. l) in front of the printing machine and moved step by step by means of a suitable indexing sprocket mechanism 54a (Figs. 1, 4, 6 and 10) across the printing line of action A, the record sheet having side indexing perforations 55 for the purpose. After being printed, the record sheet 16 is returned to a second tray stand 56 above the input tray stand 54. The record sheet 16 may consist of a multiplicity of layers interleaved with carbon tissues to permit the production of a number of carbon copies.

The printing device 53 comprises a spring-pressed plunger 57 (Figs. 4 and 6) in a housing 58 carried on a carriage 59. with wheels 60 permitting movement of the plunger step by step along supporting rails 61. The

carriage 59 is driven step bystepby an intermittent drive 62 similar to that for driving the selector, ring 31.. The printing plunger 57 acts on one side of the course of the record sheet 16, while on. the "opposite side is located an inked ribbon 64 wound-at its endson two spools 65, one of which winds and the other unwinds, as in a conventional typewriter. After. the printing ,of a line across the record sheet 16, the ribbon 64 is fed automatically a distance equivalent to a' printed line to present a fresh section of the ribbon forthe printing of the next line. A reversing mechanism 59a (Fig. reverses the operation of the ribbon spools 65, when the ribbon has been unwound from one spool and wound on the other. 1

The plunger 57 when actuated in manner to be described, presses the record sheet 16- against the ribbon 64 and the ribbon against the selected character on the wheel 10, so that this character is imprinted on the record sheet. To operate the plunger 57 for fliis purpose, there is provided a plunger actuator bar 66 (Figs. 4 and 6) extending parallel to the shaft 12 of the wheels 10 and located opposite the projecting end of the plunger. The ends of this plunger actuator bar 66 are connected to the plungers of two solenoids 67, respectively,. these being energized in response to character-signals but being irresponsive to space function signals, as will be more fully described, When these solenoids 67 are energized upon receipt of the proper signals, the bar 66 is moved into engagement with the printing plunger 57 and this moves the plunger into position to print the selected-character as described. These solenoids 67 may be energized directly by the information. pulses after the necessary amplification or may be in a separate circuitand closed by a relay switch controlled by the pulses. A synchronized delay is introduced between receptio of a character signal and operation of the printing plunger 57 equivalent to a definite number of character and space function units, in order to allow a printing wheel 10 sufficient time to be positioned before printing of the selected character thereon takes place. In the specific form shown, the delay is made equivalent to 35 character and space function units and may be effected by a counting device or register of any type'well known in the art. For'the purpose of illustration, there is shownin basic form, a counting device 70 (Figs. 9 and,l0) known as a magnetic shift register. Thismagnetic shiftregister 70 comprises a plurality of magnetically saturable cores 71, the number corresponding to the amount of delay required. In the specific form illustrated, for a delay equivalent to that necessary to receive 35 characters and space function signals, 35 of such: cores are provided connected in series. The space functionsignalsserve to provide the necessary spaces between words or between certain characters where required. i

Although magnetic shift registers, per se, are well known, a suitable type is shown in its basic form in Fig. 9 and is described briefly herein: A core made of magnetic material with -a substantially rectangular hysteresis loop has two. stablev reproducible states, namely, a negative saturation state and a positive saturation state. Once magnetized to one of these states by an applied field strength pulse of positive or negative amplitude, the core will remain indefinitely in that state Without application of external power. Use is made of these two states to store a pulse. Themagneticshift register 70 of the present invention is made up of a number of these magnetic cores 71, so interconnected that pulses can be stored and unidirectionally transferred from one core to another. g

Fig. 9 shows a four core magnetic shift register. for purpose of explanation and illustration, but it must be understood that the number ofcores 71,de pends on the amount of delay required (35 cores in the specific embodiment illustrated). Each core 71 has three windings: Au

input winding 72, an output winding 73 and an adyauce,

or shift. winding 74, the input winding of the first core in the particular application of the present invention being adapted to receive input character and space function signals in wave voltage form of generally rectangular configuration. 'The advance winding 74 consists of advance A and advance B driver, these comprising receiver tube type pentodes normally cut off. When turned on, the advance A driver tube causes a magnetizing current to flow through the serially connected advance windings of the odd numbered cores 71. This current is in such direction as to drive these odd numbered cores to the negative saturation state. The advance B driver is similarly connected to the even numbered cores 71. The pulses sent through the advance windings A and B are in wave voltage form of rectangular configuration and are synchronized in time relation with the pulses fed into the input windings 72 of the first core 71, as for example by a synchronized pulse generator. These advance pulses follow the input pulses by a very slight delay running to a small fraction of a second.

In the description of the operation of the magnetic shift register that follows, it is assumed thatall four cores 71 illustrated are in negative saturation state initially. At the time T1, the input driver 72 and the advance B drive are pulsed. The input driver 72 causes the first core 71 to change to positive saturation flux density. At the end of the input driver current pulse, the flux in thefirst core 71 changes to the positive saturation state. The second and fourth cores 71 remain in the negative saturation state. At time T2, the advance A driver is pulsed and the first core is returned to negative saturation flux density. The large charge in flux in going from positive to negative saturation state, produces a voltage at the output winding 73 of the first core 71 which forces current through the forward direction of the series rectifier in said output Winding into the input winding 72 of the second core 71, magnetizing it to the positive saturation state. At time T3, the advance B driver current is turned on again, and the second core 71 is returned to the negative saturation state. The third core 71 is driven to positive saturation state by the large change in the flux in the second core 71. At time T4, the advance A driver current transfers in effect the input pulse from the third core 71 to the fourth core 71. In this manner, the input pulse initially read into the first core 71 has been transferred by the operation described to the fourth core 71 by successive applications of the advance A and advance B current pulses.

In the case where the magnetic shift register 70 has 35 cores 71 interconnected as described, the effect of the first information pulse into the first of the cores 71 is shifted successively through the 35 cores under the influence of the successive shift or advance pulses, so that the effect of an information pulse read into the register will be read out after a delay equivalent to the time required to receive 35 information pulses.

The information pulses corresponding to character signals are readout from the register 70 and serve to actuate the plunger actuator bar 66 through energization of its solenoids 67, into position to press the plunger 57 for printing. The information pulses corresponding to the space function signals are not discharged from the register 70, since no operation of the plunger actuator bar 66 takes place in response thereto; The information pulses corresponding to the space function signals may therefore be in potential opposite to the information pulses corresponding to the characters, or may simply consist in pauses, so as to have no effect on the register except to incorporate into the register a condition which will be evidenced by a lack of output pulse therefrom,

' when in the order of sequence, such pulses should be at the forward end of the sequence. Themagnetic shift register 70 thereby serves not only as a device for delay-..

ing the action of an information signal but also as a memory device to render effective certain signals and render ineffective certain signals, when the time for reading out such signals arrives.

The forty-eight pairs of leads transmitting the different character pulses from the transmitter, as described above, and the pair of leads transmitting the space function pulses from the transmitter are connected to the input winding 72 of the first core 71 of the delay register 70, so that any time a pulse comes in from the transmitter through any one of the 49 pairs of leads, these are transmitted to the input winding 72 of the first core 71, the form and relationship of the character and space function pulses being as described above.

In conjunction with the printing machine of the present invention, there is employed a second delay counter or register 70a (Fig. located at the inlet side of the drive 62 for the printing plunger 57 for controlling the operation of this drive. This delay register 7011 may be similar to the delay register 70, except that the register 70a discharges both character and space function pulses after the requisite delay corresponding to that inherent in the delay register 70, i. e. the delay of character and space function units. The reason that the register 70a discharges every character pulse and space function pulse fed into it after the requisite delay, is that the plunger 57 which is controlled from the output of this register, moves step by step from wheel to wheel in synchronism with the selector ring 31 through the action of both types of pulses but with a lag which is maintained constant.

To operate the delay register 70a so that it discharges every information pulse fed into it, whether of the character or space function type, the input space function pulses fed into the register is of potential the same as that of the character signals. Therefore two signals are generated for every space function required, a positive pulse and a negative pulse, one corresponding in potential to that of the characters being sent to the delay for example, it is desired to start a new line of printing before the last line of printing of the previous line has reached the right-hand margin set for said selection, a line function signal is transmitted to the reversing gear unit of the drive 44 for the selector ring 31, causing said selector ring to reverse immediately back to its present left-hand margin. The line function signal is also transmitted to the reversing gear unit of the drive 62 for the printing plunger 57, but since this printing plunger lags behind the selector ring 31 by an interval equivalent to 35 character and space function units, the effect of this line function signal upon the reversing gear unit of the drive 62 to the printing plunger 57 must be delayed to the extent of that interval, to permit the printing plunger to complete its printing of the characters already selected on the last line. For that purpose, the third delayed counter or register 70!) is employed, the line function signal being fed into this register as an input information pulse. This register 70b may be similar to the register 70aand has lines 78 from the sources of the character signal and space function signal, which are normally opened but which are automatically closed through suitable switches and controls upon reception of a line function signal, to transmit subsequent character signal and space function signals to said register and to cause thereby the line function pulse initially fed into said register to be transmitted through successive cores in the register, until upon the receipt of the 35th input information signal, the line function pulse is discharged to reverse the printing plunger 57 towards the left. By that time, the printing plunger 57 will have completed its printing operations on the selections made on the last line and is ready to move to the left to the next line.

.Upon discharge of the line function pulse from the delay register 70b, the lines 78 from the sources of the character signals and the space function signals are automatically opened through switches or other controls, and the network of .the register set into condition to expunge the information pulses fed thereinto subsequent to the line function pulse, so that the next line function pulse will find the delay register cleared of all prior information pulses.

As another alternative, the lead lines 78 from the sources of information signals may be continuously closed during operation, but these signals may be converted into the same polarity as the shift pulses fed into the register 70b, so that they are not discharged from the register but hold their place in the sequence of stored pulses in the register, while the line function signal is of a polarity opposite from that of the shift pulses, so that only the shift pulses are discharged from the register after the delay inherent in the register.

The line advance of the paper record sheet 16 is made automatically through the indexing sprocket feed mechanism 54a (Figs. 4, 6 and 10). The feed of the ribbon 64 is synchronized with this paper line advance feed mechanism 54a to cause the ribbon to be fed a distance at least equal to that of a printing line, at the end of each line printing operation. Movement of the sprocket feed mechanism 54a is synchronized with the return of the printing plunger 57 to the left-hand margin for printing a new line. The return of the printing plunger 57 is an automatic function of a right-hand margin signal generated when the plunger reaches a preset right-hand margin. This return of the printing plunger 57 can be effected at any time before it reaches the preset right-hand margin by sending a line function pulse to the reversing gear unit of the drive 62 of the printing plunger 57 through the delay register 70b as already described.

There are two controls which intercept the line advance process in order to assure practical operations. These are a multiple line feed adjustment 81 (Fig. 10) for the paper line feed mechanism 54a and a fold skip control 82 coupled to this line feed mechanism. The purpose of the multiple line feed adjustment 81 is to provide single, double, or triple line feeding controlled by a dial indicator accessible to the operator. The fold skip control 82 functions to provide automatically adequate spacing in the place where the folds occur in the fan-fold paper sheet 16. This fold skip control 82 prevents the printing of characters close to the bottom and top of the individual pages and may be operated automatically by sending a line function pulse at the proper time to effect the line skipping operation described. The output of the delay register 70b for that purpose, not only controls the reversal of the reversing gear unit of the drive 62 for the printing plunger 57, as already described, but also controls the operation of the fold skip control 82 and the paper line feed mechanism 5411 as regulated by the adjustment 81.

The different switches, trips, adjustments and controls for effecting the line feed, ribbon feed and adjustments in these feeds may be of the type conventionally employed in typewriters.

As far as certain aspects of the invention are concerned, the use of a special line function signal for changing to a new line before selection to the preset right-hand margin is made, may be dispensed with and its function carried out by the use of space function signals which may be repeated to bring the selector ring 31 to its preset right-hand margin without character selection, whereupon the controls automatically operable when the selector ring reaches this margin take over to cause the riext line shift.

When return of a selector ring 31 is indicated, either because the ring 31 reaches the preset right-hand margin or because of the receipt of a line function signal, the selector ring 31 returns towards its left-hand margin for the next line selection. This return is effected through operation of the reversing gear unit 45 and through the Geneva mechanism 46. If desired, the return of the selector ring 31 may be effected through continuous movement and therefore more quickly than during its forward selecting movement, by by-passing automatically the Geneva mechanism 46 when return of the selector ring 31 is indicated. This could be effected by an arrangement, which in synchronism with the reversal of the gear unit 45 connects the output of this unit directly to the drive sprocket 42 of the drive 44.

During the return movement of the selector ring 31, it is desirable to interrupt the transmission of input information pulses. To that end, an input stop signal is generated by a control device 85 (Fig. 10) as a function of the arrival of the selector ring 31 at its preset righthand margin or the receipt of a line function signal. This input stop signal automatically sent to the information transmitter halts transmission of input character and space pulses for sufficient time to allow the selector ring 31 to return. During the return of the selector ring 31 and the resulting pause in the transmission of information signals, the feed operation of the printing plunger 57 and the printing operation of the plunger actuator bar 66 are interrupted by the absence of these signals. Upon completion of the shift of the selector ring 31 to the left-hand margin, an input start signal is automatically sent out by a control device 86 to the transmitter, whereupon the transmission of character and space function signals is resumed. This resumption in the transmission of information signals causes the selector ring 31 to resume selection of the next line, while the feed operation of the printing plunger 57 and the printing operation of the plunger actuator bar 66 are resumed to complete printing on the prior uncompleted line. When the printting plunger 57 reaches its preset right-hand margin corresponding to the preset right-hand margin of the selector ring 31 or reaches the limiting point determined by the transmission of a line function signal, the input stop signal device 85 generates an input stop signal which stops transmission of character and space function signals. At the same time, the reversing gear-unit of the feed drive 62 for the printing plunger 57 is operated to reverse the printing plunger towards the left. During this return movement of the printing plunger 57, the absence of incoming character and space function signals also interrupts the selector ring 31 in its selection of characters for the next line.

When the printing plunger 57 reaches its preset lefthand margin, an input stop signal is automatically sent out by the control device 86 to the information transmitter, causing resumption in the transmission of the character and space function signals from the information transmitter and thereby causing resumption in the operation of the selector ring 31 and the printlng plunger 57. v

The interrupting operations described through the stop signal control device 85 and the start signal control 86 serve to maintain the predetermined lag offset equlvalent to 35 character and space function units between the selector ring 31 and the printing plunger 57 during operations through successive printing lines.

' The printing machine of the present invention has a margin and tabulating control device 90 (Fig. 10) by which the margin of the lines may be preset or by which the spacing of characters to form tabular listings can be controlled either locally or remotely. For local operations, a margin and tabulating control panel 91 is employed having 'knobs and indicators to permit manual setup of the margins of the line or of the'spacings of tabular listings when such are desired. When a preset right-hand margin is reached, a local signal is generated and this causes the selector ring 31 to shift to the left-hand margin as described. This right-hand margin for line. printingis set up manually on the panel 91 for the margin.

and tabulating control device 90, to afford a maximum line corresponding in length to the distance occupied by all the printing wheels 10, corresponding to the spacing of 70 characters in the specific example described.

Where tabular listings are desired, the left-hand boundary of each tabular column is set manually in the margin and tabulating control panel 91. Transmission of character and space function pulses positions the characters relative to these left-hand column boundaries. Upon receipt of a tabulating signal, the tabulating control device 90, acting upon the selector ring 31, causes said selector ring to shift from the right-hand boundary of one tabular column to the left-hand margin of the next tabular column. Due to the interval required to effect this shift, the tabulating signal is also transmitted to the input stop control device to hold up the transmission of input information during this interval. This stops the operation of the printing plunger 57. After the required interval, an input start signal is supplied by the tabulating control device to the input start control device 86 causing resumption in the transmission of the character and space signals. This causes the selector ring 31 to start its-selecting operation on the next column and the printing plunger 57 to finish its printing operation on a previous column. When the printing plunger 57 reaches the right-hand boundary of the column it is operating on, .asignal from the tabulating control device 90 causes the plunger 57 to shift to the left-hand boundary of the next column. During this shift, the transmission of character and space function signals is interrupted through the action of the input stop control device 85 and resumed through the input start control device 86, as already described.

For remote control, some remote device may have information, perhaps manually inserted, as to the boundaries of each tabular column. Signals indicating the beginning and end of each column would be transmitted from the remote device to the tabulating control device 90, thus controlling column spacing. The printing machine, except the transmitter for the information signals, is enclosed in a casing 92 (Figs. 1, 2 and 3) having hinged covers 93 and 94 by which access to the lower and intermediate parts of the machine, such as the printing mechanism and wiring may be gained. Ready access to the upper part of the machine and particularly ,to the printing wheels 10 and the associated selector ring 31 and positioning bar device 36 may be gained through a transparent top cover 95 hinged at its back. Dials, knobs or indicators 96 for margin and tabulating adjustments and settings and for all other adjustments described and/or required are made accessible on the side of the casing 92.

Although the operation of the printing machine is believed obvious from the foregoing description, it is herein summarized briefly:

At the beginning of operations, the selector ring 31 (Figs. 4, 5 and 6 and 10) and the printing plunger 57 are in position at the extreme left opposite the end printing wheel 10 and the wheels are all immobilized from the previous operation, while the shaft 12 is rotating continuously. After a character signal comes in from the transmitter, it causes immediate energization of the solenoids 52 of the positioningbar 51 corresponding to the particular character represented by that signal and movement of this bar radially inwardly in position to press inwardly the plunger 34 on the selector ring 31 corresponding to that character. This causes the stop pin 22 radially alined with the depressed plunger 34 and located on the stop pin guide 21 of the first wheel 10, to be moved radially inwardly into the recess 17 of this wheel and'in the path of its stop 18. This inward movement cf the selected stop pin 22 causes the release through thejock bar 25 of the stop pin 22 depressed from a 11 previous operation, thereby freeing the wheel for rotation under the influence of the continuously rotating shaft 12, until the stop 18 reaches the newly depressed stop pin 22, whereupon the wheel stops. In this new position, the selected character will be on the line of action A of the printing plunger 57.

While the first character signal is operating to effect selection of the first character on the first wheel 10 as described, the signal is also being transmitted to the drive of the selector ring 31 and after the selected stop pin 22 associated with the first wheel 10 has been depressed, the selector ring 31 under the influence of this first character signal moves the selector ring one step into position opposite the second wheel 10 which has been immobilized by a previous selecting operation.

The first character signal is also impressed on the delay registers 70 and 70a and stored therein, so that it has no effect on the drive of the printing plunger 57 or on the plunger actuator bar 66. As a result, the printing plunger 57 remains in position opposite the first printing wheel 10.

The operations in response to successive character signals are repeated without effect on the drive of the printing plunger 57 or on the plunger actuator bar 66, the signals being stored in the delay registers 70 and 70a and simultaneously acting on the positioning bars 51 to effect selection of the characters on the wheels 10 successively and movement of the selector ring 31 from wheel to wheel. Not only are the character signals stored in the delay registers 70 and 70!: but also the space function signals. These space function signals are transmitted to the drive 44 of the selector ring 31 to move the selector ring through corresponding steps but cause no selection in the corresponding 'wheels, since the spaces on the record sheet 16 opposite the latter wheels are retained unprinted to present the spaces required, as for example between words.

Upon receipt of the 35th character and space function signals, the first signal which was transmitted to the delay register 70 emerges from said register and if it corresponds to a character, it causes energization of the solenoids 67 of the plunger actuator bar 66 and moves the actuator bar in position to press the printing plunger 57 and thereby imprint on the record sheet 16 the character selected on the first wheel 10. At the same time, the first signal transmitted to the delay register 70a emerges from this register and starts the drive 62 for the printing plunger 57 operating to cause it to move opposite the second wheel after the printing from the first wheel has been completed as described. This operation is continued through successive signals after the 35th signal, so that the selector ring 31 is ahead of the printing plunger 57 to an extent equivalent to 35 wheels, thereby giving the wheels ample time to accelerate or decelerate. As a result, the wheels 10 need not operate at high speed but can operate at comparatively low speed, while attaining printing speeds as high as 100 characters per second.

If, in the order of sequence, a space function signal should be emerging from the delay register 70, this signal due to the memory characteristics of the register as described does not emerge, so that for the corresponding interval, no action takes place on the plunger actuator bar 66 and no printing takes place opposite the wheel 10 where a space is desired to be left on the record sheet 16. However, the space function signals do emerge from the delay register 70a in proper sequence, so that the drive for the printing plunger 57 is actuated for a step movement, both from the character signals as well as the space function signals. a

When the selector ring 31 reaches the preset righthand margin of the record sheet 16, the drive for the said ring is reversed and the selector ring returned towards the left. At the same time, an input stop signal is sent out from the stop signal control 85 to the transmitter interrupting further transmission of signals untilthe selector ring 31'reaches its left-hand margin. The absence of any signals immobilizes the printing plunger 57 and the plunger actuator bar 66. When the selector ring 31 reaches the preset left-hand margin of the record sheet 16, a signal from the input start control 86 resumes the transmission of information signals, whereupon the selector ring 31 starts selections for the next line, while the printing plunger 57 finishes imprinting characters selected for the previous line. When the printing plunger 57 reaches the preset right marginal position, it is returned towards the left with attendant interruptions and resumption of signals through the action of the stop and start controls and 86, so that the selection is stopped during the shifting of the printing plunger and resumed after shifting is completed. In this manner, the delay offset relationship between the selector ring 31 and the printing plunger 57 is maintained through successive line operations.

Upon receipt of a line function signal, the operation is similar to that described in connection with the shifting of the selector ring 31 and the printing plunger 57 upon reaching the preset right-hand margin of the record sheet 16.

While the invention has been described with particular reference to a specific embodiment, it is to be understood that it is not to be limited thereto, but is to be construed broadly and restricted solely by the scope of the appended claims.

What is claimed is:

l. A printer comprising a plurality of similar coaxial wheels, each bearing a series of characters, a shaft, means connecting said wheels for rotation with said shaft and operable to permit said wheels to be stopped independently of each other, selector means operable on said wheels in succession to stop said wheels in position to bring selected characters along a printing line, and printing means following the operation of said selector means and operable to imprint the selected characters in succession positioned along said line, and means for retarding the operation of said printing means in relation to the operation of said selector means, to interpose a phasic offset between the operation of the selector means and that of the printing means equivalent to a predetermined number of character bearing wheels.

2. A printer comprising a deck of similar coaxial wheels, each bearing on its periphery a series of characters, a drive shaft passing through the center of said wheels and adapted to be driven continuously, slip connections between said shaft and said wheelsfcausing said wheels to rotate with said shaft when said wheels are not impeded by selection and permitting said wheels to be stopped by selection independently of each other, while allowing the shaft to continue its rotation, 21 selector device movable along the deck of character beaning wheels by the reception of information signals and in synchronism with the reception of said signals, to bring said selector device opposite said wheels in succession, means operable by said selector device as said selector device moves opposite said wheels for stopping said wheels in succession and in position to bring selected characters on a printing line along the deck of wheels, a printing device responsive to the reception of information signals and following the operation of said selector device along said line to imprint the selector character in succession positioned along said line, and a delay register for receiving information signals and for lagging their transmission to the printing device by an extent equivalent to a predetermined number of wheels, whereby said printing device is phasically offset in its operation from said selector device by said pre determined number of wheels.

3. A printer comprising a series of similar coaxial wheels, each bearing on its periphery a plurality of characters, a drive shaft for said wheels adapted to be driven continuously, slip connections between said shaft and 13 said wheels causing said wheels to rotate with said shaft when said wheels are not impeded by selection and permitting said wheels to be stopped by selection independently of each other, while allowing the shaft to continue its rotation, a stop pin guide partially encircling each wheel and carrying a series of stop pins, each of said wheels having a stop adapted to move into engagement with a stop pin, when said stop pin has been actuated by selection and to cause thereby the wheel to stop in an angular position in which the character corresponding to the actuated pin lies on a predetermined line along the series of wheels, selector means movable from stop pin guide to stop pin guide in response to the reception of information signals, for actuating a selected stop pin in each guide according to the signal received for said guide, and a printing device following the operation of said selector means and operable to imprint the selected characters in succession positioned along said line.

4. A printer comprising a deck of similar coaxial wheels, each bearing on its periphery a series of characters, a drive shaft for said wheels adapted to be driven continuously, slip connections between said shaft and said wheels causing said wheels to rotate with said shaft when said wheels are not impeded by selection and permitting said wheels to be stopped by selection independently of each other, while allowing the shaft to continue its rotation, a stop pin guide partially encircling each wheel and carrying a series of stop pins guided for depressed movement radially inwardly towards the corresponding wheel, each of said wheels carrying a stop, said pins in depressed positions lying in the paths of rotation of the stops of the corresponding wheels, whereby said wheels are stopped by the depressed stop pins in angular positions in which the characters corresponding to the depressed pins lie on a predetermined line along the deck of wheels, a selector arm mounted for movement along the deck of wheels and adapted to encircle said stop pin guides successively as said selector arm is so moved, said selector arm carrying a series of plungers corresponding to the stop pins in each guide and adapted when depressed radially inwardly to depress the corresponding stop pins, plunger actuator bars extending substantially parallel along the deck of wheels and in an arcuate row around said selector arm opposite said plungers respectively, said plunger actuator bars being mounted to move into position when actuated to depress the corresponding plungers, means responsive to the re ception of each character signal from 'a transmitter for moving said selector arm one step into selecting position from one stop pin guide to the next, and for actuating one of said plunger actuator bars corresponding to the character represented by the signal transmitted, whereby said wheels are stopped successively with the selected characters thereon positioned on said line, and a printing device operable along said line to imprint the selected characters positioned therealong.

5. A printer comprising a plurality of similar coaxial wheels, each bearing a series of characters, a shaft, means connecting said shaft for rotation with said shaft and operable to permit said wheels to be stopped independently of each other, a selector device, means for moving said selector device one step from position opposite one wheel to position opposite the next wheel as character signals are received in succession from a transmitter, means operable by said selector device as said selector device moves opposite said wheels for stopping the wheels in succession in response to said signals in angular positions to bring the characters corresponding to the signals into printing positions, a printing device, means responsive to the reception of character signals for movmg said printing device one step from printing position wrthrespect to the selected character on one wheel to printing position with respect to the selected character on the next wheel, and means for delaying transmission of character signals to said printing device to cause printing operations to lag behind selecting operations by a predetermined number of wheels. I I I I 6. A printer as described in claim 5, wherein there are provided means'forreturning the selector device to its starting position when the end of a line is indicated, means for interrupting the transmission of character signals to said selector device and to said printingdevice, while the selector device is returning to its starting position, means for resuming transmission of character signals after the selector device has reached starting posi-' tion, means for returning the printing device to its starting position when the printing of all selected characters on a line has been completed, means for interrupting the transmission of character signals to said selector device and to said printing device while the printing device is returning to its starting position, and means for resuming transmission of character signals after the printing device has reached starting position.

7. A printer comprising a plurality of similar coaxial wheels, each bearing a series of characters, a shaft, means connecting said wheels for rotation with 'said shaft and operable to permit said wheels to be stopped independently of each other, a selector device, means for moving said selector device one step from position opposite one wheel to position opposite the next wheel as character and space function signals are received in succession from a transmitter, means operable by said selector device as said selector device moves opposite said wheels for stopping the wheels in succession in response to character signals in angular positions to bring the characters corresponding to the character signals into printing positions, a printing device, means responsive to the reception of character and space function signals for moving said printing device one step from one wheel to the next wheel, means for delaying transmission of character and space function signals to said printing device to cause said printing device to lag behind the selector device by a predetermined number of wheels, means responsive to the reception of a character signal for operating said printing device at any wheel to imprint the selected character from said wheel onto a record sheet, and a delay memory device for storing character and space function signals received from the transmitter and for transmitting the stored. character signals in succession to the means for operating the printing device with a lag equivalent to said predetermined number of wheels, while rendering ineffective the space function signals on the means for operating the printing device.

8. A printer comprising a plurality of similar members arranged in a row and each bearing a series of characters, selector means, means responsive to input character signals received from a transmitter for moving said selector means along the row of character bearing members and for selecting characters from each of said members in succession, printing means, means responsive to input character signals from a transmitter for moving said printing means along the row of character bearing members and for operating said printing means to imprint on a record sheet the characters selected from each of said members in succession, means for delaying the transmission of character signals from the transmitter to the means for moving and operating the printing means, whereby said printing means lags in its movements and operations behind said selector means by a predetermined number of character bearing members, means operable when the selector means reaches a predetermined margin in a line for returning said selector means to its initial position to start a new line of selection, means operable whlle said selector means is returning to its initial positron for interrupting transmission of character signals from the transmitter, means operable when the selector means reaches 1ts initial position for resuming transmiss1on of character signals from the transmitter, means operable when the printing means reaches said predetermined margin for returning said printing means to its initial position for the start of a new line, means operable while said printing means is returning towards its initial position for interrupting the transmission of character signals from the transmitter, and means operable when the printing means reaches its initial position for resuming transmission of character signals from the transmitter.

9. A printer comprising a plurality of similar memers arranged in a row and each bearing a series of characters, selector means, means responsive to input character signals for moving said selector means along the row of character bearing members and for selecting characters from each of said members in succession, printing means, means responsive to input character signals from a transmitter for moving said printing means along the row of character bearing members and for operating said printing means to imprint on a record sheet the characters selected from each of said members in succession, means for delaying the transmission of character signals from the transmitter, to the means for moving and operating the printing means, whereby said printing means lags in its movements and operations behind said selector means by a predetermined number of character bearing memhers, means responsive to an input line function signal received from the transmitter for returning said selector means to its initial position to start a new line of selection, means operable while said selector means is returning to its initial position for interrupting transmission of character signals from the transmitter, means operable when said selector means reaches its initial position for resuming transmission of character signals from the transmitter, means responsive to the input line function signal received from the transmitter, and operable after a delay equivalent to said predetermined number of character bearing members for returning said printing means to its initial position for the start of a new line, means operable while said printing means is returning towards its initial position for interrupting the transmission of character signals from the transmitter and means operable when the printing means reaches its initial position for resuming transmission of character signals from the transmitter.

10. A printer comprising a plurality of similar members arranged in a row and each bearing a series of characters, selector means, means responsive to input character signals for moving said selector means along the row of character bearing members and for selecting characters from each of said members in succession, printing means, means responsive to input character signals from a transmitter for moving said printing means along the row of character bearing members and for operating said printing means to imprint on a record sheet the characters selected from each of said members in succession, means for delaying the transmission of character signals from the transmitter to the means for moving and operating the printing means, whereby said printing means lags in its movements and operations behind said selector means by a predetermined number of character bearing members, means responsive to a tabulating signal from a transmitter for moving the selector means from the right hand margin of one column to the left hand margin of the next column, means operable while said selector means is shifting from one column to the next for interrupting transmission of character signals from the transmitter, means operable when said selector means reaches the next column for resuming transmission of character signals from the transmitter, means responsive to a tahulating signal from the transmitter and operable after a delay equivalent to said predetermined number of character bearing members for shifting said printing means from the right hand margin of one column to the left hand margin of the next column, means operable while said printing means is being so shifted for interrupting the transmission of character signals from the transmitter and means operable when the printing means reaches the next column for resuming transmission of character signals from the transmitter.

11. A printer comprising a plurality of similar memhers arranged in a row and each bearing a series of characters, selector means, means responsive to input character signals from a transmitter for moving said selector means along the row of character bearing members in succession, printing means, means responsive to input character signals from a transmitter for moving said printing means along the row of character bearing members and for operating said printing means to imprint on a record sheet the characters selected from each of said members in succession, means for delaying the transmission of character signals from the transmitter to the means for moving and operating the printing means, whereby saidprinting means lags in its movements and operations behind said selector means by a predetermined number of character bearing members, a tabulating control by which the left and right hand margins of each column on a record sheet can be preset, means operable when the selector means reaches the right-hand margin of a column set in said control for shifting the selector means from one column to the next, means operable when the selector means is so shifted for interrupting transmission of character signals from the transmitter, means operable whensaid selector means reaches the left-hand margin of the next column set in 'said control for resuming transmission of character signals from the transmitter, means operable when said printing means reaches the right-hand margin'of a column preset in said control for shifting said printing means to the left-hand margin of the next column, means operable while said printing means is being so shifted for interrupting the transmissionof character signals from the transmitter, and means operable when the printing means reaches the next column for resuming transmission of character signals from thetransmitter.

Referen cesCi ted the file of this patent UNITED STATES PATENTS 871,145 Richards Nov. 19, 1907 1,976,599 Bryce Oct. 9, 1934 2,047,505 Hausheer July 14, 1936 2,080,649 Breitling May 18, 1937 2,157,035 Torkelson, May 2, 1939 2,412,777 Kao Dec. 17, 1946 2,566,944 Last Sept. 4, 1951 2,692,551 Potter Oct. 26, 1954 2,720,832 Luning Oct. 18, 1955 2,726,601 Paris Dec. 13, 1955 2,776,618 Hartley Jan. 8, 1957 2,800,073 Block July 23, 1957 2,805,620 Rosen 'Sept. 10, 1957 2,811,102 D'evol Oct. 29, 1957 

